How should I resolve conflict bookmarks?

[chmnchiang]

When I update my local bookmarks, and there are also updates on the remote branches (graphite restacking the PRs or someone else change the same branch), after jj git fetch, it can enter a conflict state.

However, it is not clear how to deal with the conflict. I'll want to merge or at least make sure there is no difference before moving the bookmarks. The doc mentions

You may want to first either merge the conflicted targets with jj new (e.g. jj new main)
But when I run it, it shows

jj new <conflicting-branch>
Error: Name `<conflicting-branch>` is conflicted

Should I just rebase it? But not sure if this is the right thing to do when I have multiple stacked bookmarks. I want a way to unify local commit chains one-by-one, like if I have

trunk - local A - local B
      \
        remote A - remote B

I'm looking for a way that will first merge local and remote A, and then B, etc. (I think this is what git pull does?)